It is well known that data in the form of hypermedia such as hypertext is often written in a hypertext language such as HTML and arranged in web pages that are provided by a server connected through a network to a client. The client may comprise a personal computer or other processing device capable of presenting the data retrieved from the server to a user. The network may comprise the World Wide Web, which comprises many servers connected over the Internet in a web, and web pages have network addresses in the form of universal resource locators (URLs). The web pages include hyperlinks to allow the user to establish a link to other web pages, which may be located on the same or a different server, the linking being achieved by the use of a URL in the web page at the hyperlink.
Web clients typically access the hypermedia information using a browser. An overview of the World Wide Web and HTML is given in chapter 1 of “HTML 3.2 and CGI Unleashed” J. December and M. Ginsberg 1996 (ISBN 1-57521-177-7). Although HTML is usually used to prepare web pages, they can also be created in other mark-up languages. Conventional browsers such as Microsoft Explorer and Netscape Navigator include a book-marking function that allows individual web pages to be book marked. In this way, the network address for a particular web page is cached in a bookmark list so that the web page concerned can be readily located on subsequent occasions. The user may build up a significant number of bookmarks which may make the bookmark list long and confusing, so proposals have been made to categorise the bookmarks according to subject matter categories, e.g. sport, news. Conventional browsers allow bookmarks to be placed in an hierarchical folder structure, in which a main folder is linked to sub-folders. For example, the user may set up folders corresponding to web pages for the category “sport” which may be provided with sub-folders for particular types of sports individually, e.g. swimming and soccer. However, this hierarchical folder structure suffers from a disadvantage that when a particular book marked web page relates to more than one of the folder categories, it needs to be included in more than one folder to enable efficient retrieval, which results in a multiplicity of entries which undesirably take up memory space.
A number of prior art proposals have been made to categorise book marked web pages. For example, U.S. Pat. No. 6,195,657 discloses a categorisation scheme and concerns finding other categories that match a first category based on the content of the categories.
U.S. Pat. No. 6,211,871 concerns a computer that has a number of bookmark sets. These sets are not dynamic combinations that are fixed. They provide a security function that disables the computer from accessing certain sets. U.S. Pat. No. 6,243,071 concerns an electronic book that has a book marking system. Bookmark icons that can be shown on individual book marked pages are described but they are not categorised.